title: Genetic influences on cost-efficient organization of human cortical functional networks.
abstract: The human cerebral cortex is a complex network of functionally specialized regions interconnected by axonal fibers, but the organizational principles underlying cortical connectivity remain unknown. Here, we report evidence that one such principle for functional cortical networks involves finding a balance between maximizing communication efficiency and minimizing connection cost, referred to as optimization of network cost-efficiency. We measured spontaneous fluctuations of the blood oxygenation level-dependent signal using functional magnetic resonance imaging in healthy monozygotic (16 pairs) and dizygotic (13 pairs) twins and characterized cost-efficient properties of brain network functional connectivity between 1041 distinct cortical regions. At the global network level, 60% of the interindividual variance in cost-efficiency of cortical functional networks was attributable to additive genetic effects. Regionally, significant genetic effects were observed throughout the cortex in a largely bilateral pattern, including bilateral posterior cingulate and medial prefrontal cortices, dorsolateral prefrontal and superior parietal cortices, and lateral temporal and inferomedial occipital regions. Genetic effects were stronger for cost-efficiency than for other metrics considered, and were more clearly significant in functional networks operating in the 0.09-0.18 Hz frequency interval than at higher or lower frequencies. These findings are consistent with the hypothesis that brain networks evolved to satisfy competitive selection criteria of maximizing efficiency and minimizing cost, and that optimization of network cost-efficiency represents an important principle for the brain's functional organization.
authors.affiliation: Brain Mapping Unit, Behavioural & Clinical Neurosciences Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom. fornitoa@unimelb.edu.au
authors.forename: Alex
authors.initials: A
authors.lastname: Fornito
authors.forename: Andrew
authors.initials: A
authors.lastname: Zalesky
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Bassett
authors.forename: David
authors.initials: D
authors.lastname: Meunier
authors.forename: Ian
authors.initials: I
authors.lastname: Ellison-Wright
authors.forename: Murat
authors.initials: M
authors.lastname: Yücel
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Wood
authors.forename: Karen
authors.initials: K
authors.lastname: Shaw
authors.forename: Jennifer
authors.initials: J
authors.lastname: O'Connor
authors.forename: Deborah
authors.initials: D
authors.lastname: Nertney
authors.forename: Bryan J
authors.initials: BJ
authors.lastname: Mowry
authors.forename: Christos
authors.initials: C
authors.lastname: Pantelis
authors.forename: Edward T
authors.initials: ET
authors.lastname: Bullmore
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000502:physiology*; D014429:Twins, Dizygotic / Q000235:genetics*; D014430:Twins, Monozygotic / Q000235:genetics*; D055815:Young Adult